#include <stdio.h>
#include <assert.h>
 size_t my_strlen(const char*str)
 {
    const char* start = str;
    assert(str != NULL);
	while(*str !='\0')
	{
		str++;
		
		}	
 	
 	return str - start;

  } 
  
  int main()
  {
  	char arr[] = "abcdef";
  	size_t len = my_strlen(arr);
  	printf("%d\n",len);
  	 
  	 return 0;
  	
  	
  	
  }
  
